Dynamic layout management for robotics warehouse system

ABSTRACT

Embodiments implement a minispace concept to dynamically manage layout of a robotics warehouse system. The warehouse space is divided into a plurality of equally sized minispaces, each corresponding to a standard rack footprint. Each minispace is identified by tagging with a unit location ID and attribute(s) such as coordinates. Minispaces may be referenced in a task planning process flow that initially comprises determining stock and rack, followed by determining a relevant workstation. The task is then assigned to an appropriate robot, and a travel route is planned (e.g., shortest path in minispace layout). Robot actions within the route are then planned and executed by the warehouse management system according to the minispace layout. Minispaces allow a robot to identify each minispace by the tagging, and to plan the next movement accordingly. The use of minispaces may facilitate collision avoidance by grouping actions together and allowing performance of minispace locking/checking procedures.

BACKGROUND

Unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.

Warehouse storage systems have evolved to “good-to-person” schemes, in which robots move product racks to/from a human stock handler's stationary workspace. Such environments may feature a warehouse management system (WMS) that is responsible for coordinating activity of the mobile robots within the physical warehouse space.

Current WMS' may be custom designed for a specific warehouse physical layout. Thus the stock placement strategy and warehouse process flow may be specifically tailored to that particular layout. Such lack of flexibility can lead to complexity and expense in updating the WMS when the warehouse layout is to be changed (e.g., expanded). And, owing to the implicit relationship between physical layout and the WMS, the underlying location and layout of the robotics warehouse may not actually be explicitly visible to the WMS.

SUMMARY

Embodiments implement dynamic layout management for a robotics warehouse system utilizing a minispace concept. The warehouse space is divided into a plurality of equally sized minispaces, each corresponding to an area that can hold a rack of standard square dimensions. Each minispace is identified by the tagging with a unit location ID and attribute(s) such as coordinates. Minispaces may be referenced in a task planning process flow initially comprising determining stock and rack, followed by the determination of a relevant workstation. The task is then assigned to an appropriate robot, and a travel route planned (e.g., one involving a shorted path in the layout of minispaces). Robot actions within the route are then planned and executed by the warehouse management system according to the minispace layout. Minispaces allow a robot to identify each minispace by the tagging, and to plan the next movement accordingly. The use of minispaces facilitates robot collision avoidance by grouping together actions, and then performing locking and checking procedures.

The following detailed description and accompanying drawings provide a better understanding of the nature and advantages of embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a simplified diagram of a system according to an embodiment.

FIG. 2 shows a simplified flow diagram of a method according to an embodiment.

FIG. 3 shows an embodiment of a warehouse layout according to an example.

FIG. 4 shows a software solution for a model driven layout design approach according to an example.

FIG. 5 illustrates hardware of a special purpose computing machine according to an embodiment that is configured to perform robotics warehouse layout design.

FIG. 6 illustrates an example computer system.

FIG. 7 shows a simplified diagram of a dynamic layout system according to an embodiment.

FIG. 8 shows a simplified flow diagram of a dynamic layout method according to an embodiment.

FIG. 9 illustrates the minispace concept with location tagging according to an embodiment.

FIG. 10 illustrates an example warehouse layout under the minispace concept.

FIG. 11 illustrates a task planning process flow according to an embodiment.

FIG. 12 is a simplified diagram illustrating communication for Robot Action Execution.

FIG. 13 illustrates a simplified example of a route plan according to an embodiment

FIG. 14 illustrates the coordination required when forwarding to a next minispace.

FIG. 15 illustrates an example of robot action planning with collision avoidance according to an embodiment.

FIG. 16 illustrates an example of locking and checking a next minispace.

FIG. 17 illustrates robot action execution with collision avoidance.

FIG. 18 illustrates a warehouse layout change use case.

FIG. 19 illustrates an exception to the warehouse layout change use case.

FIG. 20 illustrates making a rackspace minispace change.

DETAILED DESCRIPTION

Described herein are methods and apparatuses implementing a layout design for a robotics warehouse. In the following description, for purposes of explanation, numerous examples and specific details are set forth in order to provide a thorough understanding of embodiments according to the present invention. It will be evident, however, to one skilled in the art that embodiments as defined by the claims may include some or all of the features in these examples alone or in combination with other features described below, and may further include modifications and equivalents of the features and concepts described herein.

Embodiments relate to the design of a (good-to-person) robotics warehouse, and in particular to a warehouse layout model. The warehouse layout model is interposed between a warehouse map/location model containing concrete physical location data (e.g., QR codes), and an overlying warehouse management system generally configured to interact with a robotics system. The warehouse layout model defines basic elements such as •rackspace, •rackspace block, •lane, and •workstation. Those elements may in turn be arranged into basic patterns such as •storage area, •workstation area, •entry area, and others. The layout model also includes a set of basic traveling rules governing the movement of robots in relation to the elements and patterns. The layout model serves as a translator between the generalized warehouse management system, and the location/map model specific to a particular warehouse footprint. The warehouse layout model facilitates adapting the robotic system and warehouse management system to changes as the warehouse expands.

FIG. 1 shows a simplified view of a system configured to implement resource analysis according to an embodiment. Specifically, system 100 comprises a robotics system 102 that controls the activity of robots in relation to a warehouse model environment 104. In particular, the warehouse map/location model 106 represents a specific physical location of the warehouse, for example using the position of RF sensors. The robotics system interacts with the map/location model 106 via a software program, for example utilizing Quick Response (QR) code 107.

The warehouse management system 108 is designed to interact with the robotic system. For example, the warehouse management system is configured to provide the robotics system with planned tasks 110 requiring movement, such as movement of a product rack to a stationary human stock handler at a workstation. The robotics system is in turn configured to return execution status 112 to the warehouse management system.

According to embodiments, the warehouse model environment further comprises the warehouse layout model 114. The warehouse layout model is configured to provide a basic set of elements 116, patterns 118, and movement rules 119 that are readily configurable across a variety of different possible warehouse physical footprints and robotics systems.

In particular, FIG. 1 shows the human user 120 providing instructions 121 to the warehouse layout model via a layout design platform 122. The platform in turn provides parameters 123 to the layout model to conform it to the needs of the user. As described further below in connection with the example, the layout design platform may include various features allowing:

initial design of the layout model;

management of change of the layout model (e.g., as the warehouse expands); and

deployment and testing of the layout model with the warehouse management system.

Following creation of the layout model, it may be communicated to the warehouse management system for reference in connection with purposes such as stock strategy planning, task planning routing, and execution of the robots of the robotics system.

The layout model is also communicated to a user for display. Based upon review of the warehouse layout model, the user may then provide revised instructions for creating a changed warehouse layout model to reflect updated warehouse conditions (e.g., expansion).

FIG. 2 is a flow diagram showing various actions taken in accordance with an embodiment. At 202 a warehouse location model comprising physical locations of a warehouse recognized by a robotics system (e.g., via QR codes), is provided.

At 204 a warehouse layout model template is provided comprising a plurality of elements, a plurality of patterns assembled from one or more of the plurality of elements, and robot movement rules dictated by one or more of the plurality of patterns.

At 206 instructions are received from a user to generate a warehouse layout model from the physical warehouse model.

At 208 the warehouse layout model template is applied to the physical warehouse model according to the instructions, in order to create the warehouse layout model mapping one or more of the plurality of elements, the plurality of patterns, and the robot movement rules to the physical locations.

At 210, the warehouse layout model is communicated to a warehouse management system. At 212, the warehouse layout model is displayed to a user.

At 214, updated instructions are received from a user to change the warehouse layout model. At 216 the warehouse layout model template is again applied to the physical model to generate a changed warehouse layout model.

At 218 the changed warehouse layout model is communicated to warehouse layout model and to the user for display.

In summary, the warehouse layout model serves as a bridge between the warehouse map/location model specific to a particular physical location and robotics system, and an overlying generalized warehouse management system. The layout model acts as a translator across different robotics systems, facilitating adaptation as a warehouse changes and evolves. The layout model allows the warehouse management system to customize, setup, and deploy for different customers and use cases. Embodiments allow the process of robotics warehouse design to focus upon the space of storage and productivity by number of workstations, with the warehouse management system focusing upon the planning and execution tracking with underlying robotics systems. Use of the warehouse model according to embodiments also offers ready scalability. Based upon the changes in demand for products, it becomes relatively simple to correspondingly adapt warehouse features such as available storage space and numbers of workstations.

Various details of implementing a robotics warehouse layout design according to particular embodiments, are now discussed in connection with the following example of FIGS. 3-4.

EXAMPLE

In particular, FIG. 3 shows an embodiment of a warehouse layout model according to an embodiment. In this example, the layout model 300 may be assembled from a set of basic elements and patterns.

One type of basic layout element is the rackspace block 302 comprising at least one (and typically a plurality of) rackspace(s) 304. A rackspace is the minimum square area for docking a rack which is physically moved by one robot or the docking of the robot itself.

For reasons related to accessibility, a simple rackspace block typically includes two rows of rackspaces. It is noted that the rackspace can also represent the charging area for the (battery-driven) robots.

Another type of basic layout element according to this example, is the bi-directional lane 306. As shown in FIG. 3, such a 2-way lane layout element may be arranged in the horizontal or vertical direction.

Still another type of basic layout element according to this example, is the workstation 308. The workstation marks the stationary location of a human stock handler in the layout, who is interacting with products racks brought to/from her by the robots in order to perform tasks such as picking. Other tasks can include put-away and replenish.

A warehouse layout according to this particular example may comprise a number of different basic patterns. One basic pattern type is the storage area 310.

The storage area pattern includes multiple rackspace blocks. There is at least one lane between adjacent (sibling) rackspace blocks to provide connection between them.

Another basic pattern type is the workstation area 312. This pattern includes one or more workstations. For each workstation area, there is an entry area 314. For each workstation, there are two robot lanes in the entry area providing access to the workstation.

Utilizing the basic elements and patterns just described, a warehouse layout can be modeled based upon specific requirements.

A model driven approach according to embodiments may provide the following basic rules for robot traveling.

A robot can access to the storage for docking on/off the rack.

A robot can access to the workstation for picking/put-away.

A robot shall never collide with another robot.

These basic rules establish a minimum requirement for continuous operation of a robotics warehouse according to this specific example.

Basic robot functions according to this specific example are now described.

A robot may travel in one direction at the lane. A robot travels at a particular speed (S#).

A robot travels in one direction in a specified distance.

A robot can turn right or left 90 degrees.

A robot can wait for any cross road in case it crosses paths with another robot.

A robot can wait for other robot that stops in the route or docks in the workstation.

A robot can dock on/off the rack in the rackspace.

These functions are utilized for the robot to travel and execute the task on the warehouse layout composed of the basic elements and patterns. With two right turns/two left turns, a robot can make a U turn to the opposite lane.

The following is an example of robot ported in one rackspace, navigating to execute a warehouse task with basic robot functions:

1) turn to north, proceed with S1;

2) turn left, proceed with S2;

3) turn left, proceed with S3;

4) carry rack on;

5) turn to north, proceed with S4;

6) turn right, proceed with S5;

7) turn right, proceed with S6;

8) turn left, proceed with S7;

9) turn the side of rack to the workstation;

10) wait until picking/put-away finished.

In addition to the basic layout elements and patterns described above, embodiments may include other, more advanced features. These may call for enhanced functionality of robots and/or WMS systems in order to satisfy basic rules for robot traveling.

One example of an advanced feature is a uni-directional lane. Such a single direction 1-way lane requires more advanced routing planning capability. Moreover, a bi-directional 1-way lane requires more advanced coordination of accessing the robot in the lanes in order to avoid collisions.

Another example of an advanced feature is the lane-on-rackspace. There, a robot (not carrying a rack) can travel on the rackspaces even though there are racks on them. The WMS and/or robotics system may allow planning to travel on such a lane, with a bypass capability permitting the robot to wait under the rack.

Still another example of an advanced feature is the bulk rackspace block. Specifically, a rackspace block comprising more than two rows/columns of rackspaces is a bulk rackspace block. Such a feature requires the robot to access a rackspace which is not immediately adjacent to any lane. This feature calls for the system to have advanced planning of rack placing to allow the removing from this area.

FIG. 4 shows a software solution 400 for model driven layout design according to this particular example. Specifically, referencing the basic elements and patterns, the layout design framework 402 can be provided as a design time for creating and changing the warehouse layout model 404. The layout design framework may perform mapping of a layout model component 406 to the underlying map and location technical model 408. In particular, the layout design framework ensures that the basic element and patterns are correctly applied, and that the design resulting from the model can fulfill the basic rules for robot routing and execution.

In FIG. 4 the warehouse expert 410 interacting with the layout design platform, is the individual who can help setup the layout of the warehouse based on business requirements, and ensure the deployment and implementation of the robotics system. Such a warehouse expert has knowledge of the warehouse management system 412 and provides the solution in the context of specific warehouse and business requirements. Typically, however, the warehouse expert is not required to possess detailed knowledge of the robotics system 414 itself.

Deployment of the model to the WMS via module 416, generates corresponding master/customizing content. Examples of such content can include but are not limited to:

storage types;

sections;

activity areas;

workcenters;

bins;

strategy for rackspace determinations;

routing rules; and

others.

While the particular embodiment of FIG. 4 shows the layout design platform as being separate from the WMS, this is not required. According to alternative embodiments the layout design platform can also be part of the WMS.

As shown in FIG. 4, the layout design platform includes design tools 420, one of which is the element and pattern template 422. This element and pattern template includes a number of basic elements and patterns (e.g., those described above) for usage in designing a warehouse layout. The design tool can easily drag and drop in order to compose the elements and patterns into a complete layout. The element and pattern template can also be extended to support more advanced element based on the specific capability of the robot core system and the WMS system.

The layout design platform further includes the warehouse layout design module 450. This module includes the setup of determining the layout and specifically mapping the layout model elements/patterns/rules to the warehouse map/location model.

The warehouse map and location model outlines the warehouse space and areas that a robot can access. Within these areas the map/location model sets the profile for robot location. This step may depend upon the particular underlying robot locating technology. Thus in a QR code-based system for locating robots, the location profile contains all the QR codes design within this warehouse area.

The layout design is based upon the warehouse map and location profile. The layout design uses the element and pattern template to compose the warehouse layout.

The design tool has following functions to facilitate the setup of profile and connecting to the physical warehouse:

exporting and printing of location tag-like QR codes from the profile; and

importing location tag design into the profile by robot traversal tour or directly from a file.

The layout change management module 440 manages the lifecycle of the layout model. Thus when more sales occur, workstation(s) may need to be added and/or rackspaces extended in order to provide more storage. The layout change management module can propose the transition plan to ensure the new layout model is in place for operation. The layout change management module can also perform the check to ensure the model doesn't conflict with basic rules for robot traveling.

As mentioned above, the layout design platform further includes deploy and test module 416. The design tool can activate the design model to deploy into the WMS system. For example, such deployment can ensure that the stock strategy planning 430 of the WMS is consistent with the layout design of the model. Here, the stock planning strategy plans the stock based upon the locations of the racks.

Other components of the WMS core shown in FIG. 4 include task planning and routing which plan the route travel based on the warehouse layout and map. The robots execution engine plans the robot actions, communicates with the robots, and performs execution tracking.

According to this example, the testing may mainly be for verification of the implementation for warehouse map and location profile, as well as the layout design.

The deploy and testing module generates the tasks for robots full traversal routing within the warehouse to verify the location tag/QR code.

The deploy and testing module generates the tasks for robots to dock all the racks into rackspaces for storage to verify the identification of the rack and rackspaces holding capability of racks.

The deploy and testing module generates the tasks for robots to carry to rack and traversal on the lanes to verify the pass capability of physical layout.

The deploy and testing module generates the tasks for charging to ensure the reachability of charging area.

For a newly created warehouse, full testing scope may be required. For a implementation in a changed warehouse design, only a delta part may need to be tested.

Certain embodiments may be implemented in connection with an in-memory database, with the in-memory database engine performing one or more of the roles of the design platform and/or models. Accordingly, FIG. 5 illustrates hardware of a special purpose computing machine configured to implement robotics warehouse layout according to an embodiment. In particular, computer system 501 comprises a processor 502 that is in electronic communication with a non-transitory computer-readable storage medium comprising a database 503. This computer-readable storage medium has stored thereon code 505 corresponding to a layout model. Code 504 corresponds to a map/location model. Code may be configured to reference data stored in a database of a non-transitory computer-readable storage medium, for example as may be present locally or in a remote database server. Software servers together may form a cluster or logical network of computer systems programmed with software programs that communicate with each other and work together in order to process requests.

Embodiments implement dynamic layout management for a robotics warehouse system utilizing a minispace concept. The warehouse space is divided into a plurality of equally sized minispaces, each corresponding to an area that can hold a rack of standard square dimensions. Each minispace is identified by the tagging with a unit location ID and attribute(s) such as coordinates. Minispaces may be referenced in a task planning process flow initially comprising determining stock and rack, followed by the determination of a relevant workstation. The task is then assigned to an appropriate robot, and a travel route planned (e.g., one involving a shorted path in the layout of minispaces). Robot actions within the route are then planned and executed by the warehouse management system according to the minispace layout. Minispaces allow a robot to identify each minispace by the tagging, and to plan the next movement accordingly. The use of minispaces facilitates robot collision avoidance by grouping together actions, and then performing locking and checking procedures.

FIG. 7 shows a simplified diagram of a dynamic layout system according to an embodiment. In particular, system 700 comprises WMS 702 that is in communication with robotics system 704.

The WMS may provide instructions 701 to the robotics system to cause the robots to take certain actions. The robotics system may in turn provide feedback 703 to the WMS comprising the status of actions taken (or pending). This communication between WMS and the robotics system may occur via a TCP/IP connection. As previously discussed, the robotics system may also communicate with the warehouse space through connection 705.

Together, the WMS and the robotics system are configured to interact with a warehouse space 706 that is represented by a layout model 708 and a warehouse map/location model 710. The layout model may define elements of a warehouse space such as racks 712, static workstations 714, and robot travel lanes 716.

The WMS comprises an engine 720 that is configured to reference a plurality of minispaces 722. Those minispaces may include attributes such as coordinates. The minispaces shown are in the form of a square, but this is not required and other shapes are possible.

According to certain embodiments, the minispaces may be stored in an in-memory database, with a processing power of the in-memory database engine leveraged to perform the engine function. An example of an in-memory database is the HANA in-memory database available from SAP SE of Walldorf, Germany.

The engine receives from a user 730, a task 732 implicating a product 734 of the warehouse space. In certain embodiments the task may request the workstation to store the product in a particular rack (i.e., for later retrieval). In some embodiments the task may request the workstation to pick the product from a particular rack (i.e., for shipping to a customer).

In response to receipt of the task, the engine in turn references the minispaces and the warehouse space models in order to effectively move the rack to the static workstation in order to perform the task.

Specifically, FIG. 8 shows a simplified flow diagram of a dynamic layout method according to an embodiment. At 802, the method comprises providing a warehouse space divided into a plurality of minispaces having a same dimension.

At 804, a task is received specifying a product of the warehouse space. At 806, in response to the task a plurality of minispaces is referenced to determine a rack of the warehouse space relevant to the product.

At 808, the plurality of minispaces is referenced to determine a static workstation of the warehouse space to receive the rack. At 810, the plurality of minispaces and a warehouse layout model are referenced to prepare a route plan between the rack and the static workstation.

At 812, a location map and the route plan are referenced to prepare a robot action plan to move the rack to the static workstation. At 814, the robot action plan is communicated to cause a robot to execute a series of atomic actions to deliver the rack to the static workstation.

Further details regarding the warehouse layout and mapping based on the minispace concept are now provided as follows. Typical locating technology for robot travel in the warehouse is based upon location tag recognition. The location tag may be a two-dimensional QRCode.

Behind the QRCode is its unique location ID. Normally that ID is used to identify the lane in which the robot is traveling, or the rackspace to which the robot is going to dock on a rack.

According to embodiments, warehouse space can be divided into minispaces. A minispace is the area that can hold a rack which is of standard square size.

Each minispace can be identified by the tagging with a unit location ID and a plurality of attributes for instance coordinates. FIG. 9 shows a simplified generic view of a minispace including location tagging.

Embodiments allow a robot to identify each mini space by the tagging, and to plan the next movement accordingly. A warehouse space may thus be considered to be comprised of the minispaces taken together: warehouse space={Location IDs of minispace}.

As described previously (e.g., in connection with FIG. 4), a warehouse layout model defines storage and lane regions for recognition by the WMS. The warehouse map allows robot to know its current position, and what movement to be performed in a particular direction in order to navigate to the destination. FIG. 10 is a simplified view of a warehouse layout utilizing the minispace concept. It is noted that the rack space can also represent the charging area for the robot.

Task planning and execution may be based upon the minispace concept. FIG. 11 offers a summary of a task planning process flow 1100 utilizing minispaces.

The determination of stock/rack is shown at 1102. Specifically, the warehouse task is planned from the inbound or outbound delivery request.

An outbound delivery request is from the customer to pick specific stock. The system determines the stock and rack for removal.

An inbound delivery request is to put-away stock that has been purchased from a vendor. The system determines the empty space in the rack to put-away.

A specific example of task planning and execution may involve the assignment of a task for a robot to move the Rack 101 to a workstation.

Workstation determination is shown at 1104. The workstation is determined based upon the workload and the distance to the stock/rack. Continuing with the specific example, here workstation 1 is determined.

Once the workstation and rack have been determined, the task may be broken down into the following actions:

moving the rack to a workstation;

moving the rack back to the rackspace; and

moving the rack from rackspace to rackspace.

Assigning the task to the robot for execution is shown at 1106. The particular robot selected for the task may be based upon criteria such as robot availability and proximity to the rack. Continuing with the specific example, the WMS may assign the Robot X to this task as it is the one located closest to the Rack 101

Route planning under the minispace concept is shown at 1108. After the robot is assigned with warehouse task, the WMS starts planning the route from the start point of robot to the Rackspace and then from the rackspace to the workstation or next rackspace.

The route determination is based on the warehouse layout model. FIG. 13 shows an example of a route plan 1300 comprising the following:

move East 1 minispace;

move North 2 minispaces;

move West 1 minispace;

move East 2 minispaces;

move South 7 minispaces;

move West 3 minispace.

Robot action planning under the minispace concept is shown at 1110. Based on the route planning, the task and traveling is broken down into robot atomic actions. Examples of robot atomic actions are as follows:

turn right;

turn left;

forward n# minispaces;

dock rack on;

dock rack off.

Here, the supported atomic robot action may be different depending upon the different functions of the robot. For example some robots support moving forward in any direction, and so turning right/left is not required to change the forward direction of travel. The WMS's robot action planning can establish different route action planning logic in order to translate the planned route travel and execution.

An example of robot action planning under the minispace concept, is as follows:

1. turn right (assumes robot is facing the north);

2. move forward 1 minispace;

3. turn left;

4. move forward 2 minispaces;

5. turn right;

6. move forward 1 minispace;

7. dock rack on;

8. turn right;

9. turn right;

10. move forward 2 minispaces;

11. turn right;

12. move forward 7 minispaces

13. turn left

14. move forward 3 minispaces.

Execution of robot actions is shown 1112. In particular, FIG. 12 illustrates communications between the robot core and the WMS for robot action execution.

The WMS system communicates the planned actions directly to the robot core of the assigned robot through a communication connection (e.g., TCP IP). Specifically, the WMS establishes the TCI IP connection to the robot to communicate all of the actions. During execution the robots communicate back to the WMS system, the execution status (e.g., confirmation) with location information.

The minispace concept may be utilized in collision avoidance. Specifically, two robots travelling in different directions toward a same minispace may undesirably result in collision. Where a robot core system does not include the advanced feature of colliding sensing and avoidance, the WMS may be called upon to coordinate robot movement in order to avoid collisions.

The WMS may coordinate robot forward movement to gain access to a lane, as shown in the FIG. 14. In particular, that figure shows the coordination required when forwarding the robot into a next minispace that comprises a movement lane.

In order to preclude attempted simultaneous occupation of the same minispace by multiple robots, minispaces may be locked. This locking may be accomplished in the robot actions planning phase, by breaking the action steps into groups (grp) when accessing cross-lane related minispaces.

One example of such a locking procedure may be as follows.

1) Start from the first action step;

2) if the atomic action is turn left or right, continue to check the next action step;

3) if the atomic action is a forward, check whether the next location is in left or right direction;

4) if the atomic action is in a left or right direction, group the action steps processed so far, and proceed to the next action step as new group;

5) otherwise, continue to check the next action group;

6) continue the next action step, until the last action step.

FIG. 15 shows how the robot actions planning in the example of FIG. 13 may grouped to avoid collisions according to the following:

grp# atomic robot action grp1 turn right (assume robot is facing the north) grp2 move forward 1 minispace turn left move forward 2 minispaces turn right move forward 1 minispace dock rack on # turn right # turn right grp3 move forward 1 minispace grp4 move forward 1 minispace # turn right # move forward 5 minispaces grp5 move forward 1 minispace grp6 move forward 1 minispace # turn left # move forward 3 minispaces

For the robot actions execution phase the WMS communicates to the robot, the actions group by group. After completion of execution of the first actions group the WMS performs the following steps before communicating the next group of actions:

lock the next forwarding minispace.

check that no other Robot is on the lane, and travel to the next minispace. Repeat where the distance is more than 2 minispaces.

FIG. 16 shows locking and checking the next minispace.

The role of robot action execution in connection with collision avoidance, is now described. FIG. 17 illustrates the robot action execution with collision avoidance.

The actions execution is performed one actions group after another. The WMS performs the check and lock between each two groups. During execution status notification from Robot Core, WMS also have to unlock the corresponding location.

Changing of a warehouse layout based upon the minispace concept, is now described. This minispace based layout model approach can support the layout change with minimum disruption of warehouse operation.

The warehouse layout can be changed due to one or more of the following reasons:

expansion/shrinking of storage volume;

change of warehouse stock planning or process;

exception handling.

FIG. 18 illustrates several of such warehouse layout change use cases with minispaces. FIG. 19 illustrates the exception warehouse layout change use case with minispaces.

The layout change can be categorized into following cases:

change of layout map;

expansion/shrinking of the warehouse area;

increase/decrease of work centers.

With the minispace based warehouse layout, system can calculate the change of each minispace according to the layout map change:

rackspace to be removed;

new rackspace;

change of minispace lane attributes (change of direction for instance).

FIG. 20 shows a simplified view of a rackspace minispace change. The WMS plans the layout change by creating tasks for rack internal movement from the old rackspace to be removed to the new rackspace.

Here, the WMS can also allow an expert to make small adaptation of the planned tasks in order to optimize the transition. In transition phase, the old rackspaces have not yet become lanes and old lanes are treated as new rackspaces.

Thus, there may be no route for internal movement. Under such circumstances, the user specifies the internal movement sequence to avoid such an outcome.

After racks are moved to the new rackspace, the layout is fully adapted to the new model and map. The old model and map are obsolete and may be discarded or archived.

An example computer system 600 is illustrated in FIG. 6. Computer system 610 includes a bus 605 or other communication mechanism for communicating information, and a processor 601 coupled with bus 605 for processing information. Computer system 610 also includes a memory 602 coupled to bus 605 for storing information and instructions to be executed by processor 601, including information and instructions for performing the techniques described above, for example. This memory may also be used for storing variables or other intermediate information during execution of instructions to be executed by processor 601. Possible implementations of this memory may be, but are not limited to, random access memory (RAM), read only memory (ROM), or both. A storage device 603 is also provided for storing information and instructions. Common forms of storage devices include, for example, a hard drive, a magnetic disk, an optical disk, a CD-ROM, a DVD, a flash memory, a USB memory card, or any other medium from which a computer can read. Storage device 603 may include source code, binary code, or software files for performing the techniques above, for example. Storage device and memory are both examples of computer readable mediums.

Computer system 610 may be coupled via bus 605 to a display 612, such as a cathode ray tube (CRT) or liquid crystal display (LCD), for displaying information to a computer user. An input device 611 such as a keyboard and/or mouse is coupled to bus 605 for communicating information and command selections from the user to processor 601. The combination of these components allows the user to communicate with the system. In some systems, bus 605 may be divided into multiple specialized buses.

Computer system 610 also includes a network interface 604 coupled with bus 605. Network interface 604 may provide two-way data communication between computer system 610 and the local network 620. The network interface 604 may be a digital subscriber line (DSL) or a modem to provide data communication connection over a telephone line, for example. Another example of the network interface is a local area network (LAN) card to provide a data communication connection to a compatible LAN. Wireless links are another example. In any such implementation, network interface 604 sends and receives electrical, electromagnetic, or optical signals that carry digital data streams representing various types of information.

Computer system 610 can send and receive information, including messages or other interface actions, through the network interface 604 across a local network 620, an Intranet, or the Internet 630. For a local network, computer system 610 may communicate with a plurality of other computer machines, such as server 615. Accordingly, computer system 610 and server computer systems represented by server 615 may form a cloud computing network, which may be programmed with processes described herein. In the Internet example, software components or services may reside on multiple different computer systems 610 or servers 631-635 across the network. The processes described above may be implemented on one or more servers, for example. A server 631 may transmit actions or messages from one component, through Internet 630, local network 620, and network interface 604 to a component on computer system 610. The software components and processes described above may be implemented on any computer system and send and/or receive information across a network, for example.

The above description illustrates various embodiments of the present invention along with examples of how aspects of the present invention may be implemented. The above examples and embodiments should not be deemed to be the only embodiments, and are presented to illustrate the flexibility and advantages of the present invention as defined by the following claims. Based on the above disclosure and the following claims, other arrangements, embodiments, implementations and equivalents will be evident to those skilled in the art and may be employed without departing from the spirit and scope of the invention as defined by the claims. 

What is claimed is:
 1. A computer-implemented method comprising an in-memory database engine: dividing a warehouse space into a plurality of minispaces having a same dimension; storing the plurality of minispaces in an in-memory database; storing a warehouse layout model in the in-memory database; storing a location map model in the in-memory database; referencing, in response to a task specifying a product, the plurality of minispaces to determine a rack of the warehouse space relevant to the product; referencing the plurality of minispaces to determine a static workstation of the warehouse space to receive the rack; referencing the plurality of minispaces and the warehouse layout model to prepare a route plan between the rack and the static workstation, preparation of the route plan not considering the location model; referencing the location map model, the layout model, and the route plan to prepare a robot action plan to move the rack to the static workstation; and communicating with a robotics system to cause a robot to execute atomic actions to deliver the rack to the static workstation, the communicating considering the location map model but not considering the layout model.
 2. The method as in claim 1 wherein dividing the warehouse space comprises dividing the warehouse space into a minispace comprising a square of the dimensions corresponding to a footprint of the rack.
 3. The method as in claim 1 wherein: the warehouse layout model comprises a robot travel lane; the route plan crosses the robot travel lane; and referencing the location map model and the route plan comprises grouping robot actions.
 4. The method as in claim 1 further comprising the in-memory database engine ensuring that a stock strategy planning, including the product, is consistent with the warehouse layout model.
 5. The method as in claim 1 wherein the atomic actions comprise movement and docking.
 6. The method as in claim 5 wherein the movement comprises an exclusively forward movement, and atomic actions further comprise a turn.
 7. The method as in claim 1 wherein the minispace comprises an attribute.
 8. The method as in claim 7 wherein the attribute comprises a coordinate.
 9. The method as in claim 8 wherein the coordinate comprises a quick response (QR) code.
 10. A non-transitory computer readable storage medium embodying a computer program for performing a method, said method comprising an in-memory database engine: dividing a warehouse space into a plurality of minispaces having a same dimension; storing the plurality of minispaces in an in-memory database; storing a warehouse layout model in the in-memory database; storing a location map model in the in-memory database; referencing, in response to a task specifying a product, the plurality of minispaces to determine a rack of the warehouse space relevant to the product; referencing the plurality of minispaces to determine a static workstation of the warehouse space to receive the rack; referencing the plurality of minispaces and the warehouse layout model to prepare a route plan between the rack and the static workstation, the route plan including a minispace where the route plan crosses a robot travel lane of the warehouse layout model, preparation of the route plan not considering the location model; referencing the location map model, the layout model, and the route plan to prepare a robot action plan to move the rack to the static workstation; communicating with a robotics system to cause a robot to execute atomic actions to deliver the rack to the static workstation, including locking the minispace, the communicating considering the location map model but not considering the layout model.
 11. The non-transitory computer readable storage medium as in claim 10 wherein referencing the location map and the route plan comprises grouping robot actions.
 12. The non-transitory computer readable storage medium as in claim 10 wherein dividing the warehouse space comprises dividing the warehouse space into a minispace comprising a square of the dimensions corresponding to a footprint of the rack.
 13. The non-transitory computer readable storage medium as in claim 10 wherein the minispace comprises an attribute including a quick response (QR) code.
 14. The non-transitory computer readable storage medium as in claim 10 wherein the atomic actions comprise a movement and a docking.
 15. The non-transitory computer readable storage medium as in claim 10 wherein the method further comprises the in-memory database engine ensuring that a stock strategy planning including the product, is consistent with the warehouse layout model.
 16. A computer system comprising: one or more processors; a software program, executable on said computer system, the software program configured to cause an in-memory database engine of an in-memory database to: receive a task specifying a product in a warehouse space; in response to the task, reference a plurality of minispaces stored in the in-memory database, to determine a rack of the warehouse space relevant to the product; store a warehouse layout model in the in-memory database; store a location map model in the in-memory database; reference the plurality of minispaces to determine a static workstation of the warehouse space to receive the rack; reference the plurality of minispaces and the warehouse layout model to prepare a route plan between the rack and the static workstation, preparation of the route plan not considering the location model; reference the location map model, the layout model, and the route plan to prepare a robot action plan to move the rack to the static workstation; communicate with a robotics system to cause a robot to execute a series of atomic actions to deliver the rack to the static workstation, the communicating considering the location map model but not considering the layout model.
 17. The computer system as in claim 16 wherein each of the plurality of minispaces comprises an attribute including a coordinate.
 18. The computer system as in claim 17 wherein the coordinate comprises a quick response (QR) code.
 19. The computer system as in claim 16 wherein: the warehouse layout model comprises a robot travel lane; the route plan crosses the robot travel lane; and referencing the location map model and the route plan comprises grouping robot actions.
 20. The computer system as in claim 16, further comprising the in-memory database engine ensuring that a stock strategy planning including the product, is consistent with the warehouse layout model. 